Plans for the next year's research are: 1) protocotype of the brain state analyzer now being used in Neuro ICU will be replaced by a newer model. This equipment will required very little manual control for operation. There will be on equals line automatic statistical analysis with immediate display of Z transforms of the EEG frequency spectrum and averaged evoked potentials to visual, auditory and somatosensory stimuli in a histogram form for the management and study of the severely brain injured patient. 2) Cats with electrolytic mesencephalic lesions will have sequential determinants of their brain stem vectors which are the resultant of the evoked response to visual, auditory and somatosensory stimuli. The electrophysiological changes as the cats recover from their lesions is a model of the recovery as seen in patients who recover from brain stem injury due to head injury. This data will provide a basic understanding of the relationship between brain stem pathology and the resultant electrophysiological changes. x) Xenon studies developed towards determination of the regulation of the cerebral blood flow and oxygen metabolism by non-invasive techniques have been developed through equipment design and actual development of equipment. 4) Brain state vector will be utilized to monitor patient to other forms of management, and application of barbiturate therapy in patients with severe head injury will be studied.